Heaving plug for well casings



. K ril 20,1926.

. 135815442 J. L. HAWKINS .nmvms PLUG FI'OR WELL ,CASINGS Filed Jan. 20,1925 Fig.

Patented A 20 19276. I

. UNITED sr TEs JESSE Louis nawxms; or BAKERSFIELD, CALIFORNIA.

w i g HE AVING PLUG FOB) wEL'LoAsrnGs,

Application filedjanuary 2o,.1e2"5. 'Serial No. 3.63;. L

Toa'ZZ whom it mayomwern 1 H 1 Be it known that I, JESSE LOUIS HAWKINS,a citizen of the United States, residing :at

Bakersfield, in the county of Kern and State of California, haveinvented certain newand useful Improvements. in Heavmg Plugs for lVVellCasings, of'whichthe following is ,a

specification. I j n a My inventlon relatestodevices commonly known ;inthe art as .heavingiplugs7 and which are placed at the bottom of anoilwell,-to seal the bottom, of the casing. .The purpose of the plugzistoprevent the gas, present in such wells,.from.forcing or heaving sand orother formation into the bottom of the well and up into the casing.Instances have come under my observation where several hundred feet ofsand have been heaved into a well through the failure of the heavingplug.

A heaving plug, to be successful, must not only be capable of easyadjustment to and from engagement in position, but must also be adaptedfor dislodgment, and removal when it becomes necessary or desirable toredrill the well or to remove the casing.

To provide a plug having these desirable features is the object of myinvention, and to this end my invention consists in the novel heavingplug which I shall hereinafter fully describe, it being understood thatchanges in structure, form and proportion may be made within the scopeof the claims hereunto appended without departing from the spirit of theinvention.

Referring to the accompanying drawings Fig. 1 is an elevation of myheaving plug.

Fig. 2 is a vertical section of the plug on the line 22 of Fig. 1,showing also in vertical section the application to the mandrel top ofthe plug of the combination socket of a fishing tool to be used forremoving the plug when necessary.

Fig. 3 is a cross section on the line 3-3 of Fig. 1. n

Fig. 4 is a partial section of the plug showing the position of theslips entering the well.

The plug is a light hollow cast-iron shell and comprises a body portion1, the bottom of which is preferably open, as seen in Fig. 2, and a neckportion or mandrel-like top 2, with closed upper end.

In the shell wall around its circumference, say for example atequidistant points are 4cast intothe plugbo dy. 1 1

a h slip. Danna 3.21 Within theshell backjof each. opening is a wroughtiron pin Pivotally mountedupon each is a slip 5. In practice the slip ismade from apiece of round steel, and has ageneral segmental shape,withteeth 5? on its arcuate surface, said sIipplaying through theopening 3 and adaptedto engage the casing 12, Fig. 2.

;The slip is also formed-with an abutment surfacejat 5 which coacts witha stop ,6

with which the inner of the shell is provided andwhich serves to limitthefup- .ward and. inward movement of the .slip, as

shown in Fig. 4, when the plug is being lowered in the well casing 12and is sufliciently retracted to enable it to pass down therein.

The slip is mounted upon its pin by means of a slot 7 at its'inner end,and is held-on the pin by a cotter-pin 8.

It is to be noted that the axis of movement of the slip is eccentric toits toothed surface, and is such that the center of gravity of said sliplies above the horizontal plane of its axis, whereby the projection ofthe slip to its engagement with the well casing is automatic.

The pins 4 upon which the slips are mounted are, with intention designedto .break out under sufficient arring stress imposed upon the plug. Theyare strong enough to withstand any pressure to which the plug may besubjected from below, and yet weak enough to shear off or break out ofthe casting and drop down inside, if the plug be jarred, and thus freethe slips and enable the plug to be withdrawn from the well.

In order to thus jar the plug and to remove it, the upper or neck part2of the plug is made mandrel-like and is formed with a. circumferentialseries of engaging wickers or ribs 9. This adapts it to be caught by theslips 10 of a combination slip socket 11 of a fishing tool 11, as shownin Fig. 2.

When such engagement is effected and the ing through said openings; andpivotal mountings carried -by and within the shell, one for each slip,said mountings being disruptable under jarring stress imposed upon saidshell.

2. A heaving plug for well-casings comprising a hollow shell havingopenings in its side walls; casing-engaging slips func tioning throughsaid openings; and pins carried by andwithin the shell behind andproximate to said openings, one pin for and pivotally carrying one slip,said pins being mounted and fashioned to break out under jarring stressimposed upon said shell.

3. A heaving plug for well-casings comprising a hollow shell having itslower end open and its upper end closed said upper end being formedmandrel-like to receive the socket of a fishing tool and provided withmeans for engagement with said socket,

said shell having openings in its side Walls; casing-engaging slipsfunctioning through said openings; and pins carried by and withadaptingthem for automaticplay through said openings and for limiting abutmentagainst the interior stops of the shell, said pins being fashioned andmounted to break out under jarring stress imposed upon said shell, torelease the slips and permit the removal of the plug. r

In testimony whereof I have signed my name to this specification. r

JESSE LOUIS HAWKINS.

